Most of agricultural task vehicles, such as tractor, are supplied with driving power and task power through a diesel engine.
The diesel engine refers to a reciprocal movement type internal combustion engine that is driven by compression and ignition using diesel oil or heavy oil as fuel. The diesel engine is excellent in durability, but it is disadvantageous in that it discharges serious nitrogen oxide (NOx) and particulate matters (PM) that have a catastrophic effect on air pollution as compared with a gasoline engine.
Accordingly, each country is strengthening exhaust gas regulations on a diesel engine and is adopting various measures, such as delaying injection timing technically, reducing a concentration of nitrogen oxide using an exhaust gas recirculation device, and improving the combustion performance of the engine in order to reduce particulate materials.
In particular, post-processing techniques include a oxidation catalyst for purifying high-melting point hydrocarbon in particulate materials (PM), a DeNOx catalyst for decomposing and reducing nitrogen oxide (NOx) in an excess oxygen atmosphere, a diesel particulate material (smoke) filter (DPF) for filtering particulate materials (PM), etc.
From among them, the Diesel Particulate Filter (DPF) is a technique in which particulate materials discharged from a diesel engine are collected by the filter and burnt (recycled) and the recycled particulate materials are collected again and then used. Accordingly, the PDF has been known as an excellent exhaust gas post-processing device in terms of performance because it can reduce smoke by 80% or higher.
However, the DPF (hereinafter collectively called an exhaust gas post-processing device) has many difficulties in being mounted on an existing task vehicle because the DPF is bulky and heavy.
In particular, the exhaust gas post-processing device had a limited problem in that it must be installed in a position closest to the engine because it requires an exhaust gas temperature higher than a specific temperature in order to remove particulate materials certainly through combustion and or obtain sufficient catalyst activity.
Accordingly, the exhaust gas post-processing device is inevitably installed within an engine room, but it was difficult to secure an installation space because an existing engine room structure was narrow.
Furthermore, most of agricultural task vehicles generate severe traveling vibration because a high horsepower engine is mounted on the agricultural task vehicle. If fixing means for firmly supporting the exhaust gas post-processing device is not provided in the agricultural task vehicle, the exhaust gas post-processing device can be broken by a vibration impact or the purification function of the exhaust gas post-processing device can be damaged. In serious cases, the exhaust gas post-processing device departs from a fixed position during driving and collides against a peripheral structure, in particular, the engine, thereby being capable of generating a serious failure and accident.